Finite ferromagnetic clusters La1-xZnxMnO3 (x=0.05 and 0.10)

Detailed magnetic and nonlinear susceptibility measurements of the La1-xZnx MnO3 system are reported. For x = 0.05 and 0.1, a typical ferromagnetic (FM ) signal in the field-cooled curve is observed at 38 It. However, for the i nsulating antiferromagnetic (AFM) parent compound LaMnO3 and for the x = 0. 2 and 0.33 samples, the magnetization curves in the low temperature range, are smooth and flat. This observation confirms the coexistence of finite FM clusters in the insulating AFM region below the critical concentration (x( c) = 0.16) for percolation, predicted by the percolation model.